The present invention refers to a device for gaseous discharge tubular lamps that reduces the consumption of energy by 40% without varying the luminosity of the tube to which it has been applied. In addition, the ambient contamination by ultraviolet radiation is reduced.
The term ultraviolet refers to electromagnetic radiations that have a wave length between 100 and 400 nm (nanometers).
Ultraviolet rays are invisible and are classified in three bands: long waves, called radiation UV-A from 315 to 400 nm; medium length waves, radiation UV-B from 280 to 315 nm; and short wave radiation UV-C from 100 to 280 nm.
Radiation of band UV-A passes through almost all types of glass and practically does not cause any erythema (reddening of human skin). They possess the property of promoting fluorescence in certain materials and originating photo-chemical reactions in others. The radiation of band UV-B provokes erythemal effects and tanning of the skin. These radiations are employed principally in therapeutic usage (sun lamps). Radiation of band UV-C, with maximum efficacy in the region of 254 nm wage length can lead to fluorescent phenomenon in certain materials and can cause erythema and conjunctivitis.
Bands "A" and "B" pass through almost all types of glass and the short wave band "C" is the one that energizes and produces the greatest photonic effect on phosphorus, causing the emission of luminous photons.
The point of greatest production of photons is located specifically in the wave length of 253.7 nm. This effect is found in the ionized cavity of the tubes by electronic bombardment.
This effect is not absolute, and elevated percentages of other UV wave lengths are produced. These are short, medium and long wave lengths, both above and under the optimum value of 253.7. They act harmoniously in the medium and long bands reaching even the luminous range above 400 nm. This percentage of UV, with the capability of passing through the glass of the tube (which would need a much denser cover of phosphorus to discharge its energy) is wasted and does not contribute to the photonic production. This is due to the fact that an optimum luminous effect is not obtained from the fluorescent tube.
Some designs by manufacturers of fluorescent tubes are known to augment the luminous output of said tubes by placing a reflective cover inside the tube glass. However, a significant increase in the luminosity is not obtained nor is there any additional advantage.